Stone, 25, has not appeared in a game since August 31. In 25 starts prior to his deactivation, he amassed a 3.53 ERA (111 ERA+) and a 3.14 strikeout-to-walk ratio. His contributions have been worth an estimated 1.8 Wins Above Replacement, according to Baseball Reference's calculations.

Although it had been expected Stone wouldn't pitch again this season, the news throws the Dodgers' postseason rotation into further flux.

After announcing that Tyler Glasnow is expected to miss the rest of the season over the weekend, Dodgers manager Dave Roberts offered similar news Wednesday about right-hander Gavin Stone, saying the rookie star is “very unlikely” to pitch this season as he continues to battle a shoulder injury.

Gavin Stone's season-ending injury raises concerns for the Dodgers' pitching rotation as they head into the playoffs

Dodgers manager Dave Roberts announced to reporters that right-hander Gavin Stone is still experiencing shoulder soreness and is "very unlikely"

The Los Angeles Dodgers have placed pitcher Gavin Stone on the injured list with right shoulder inflammation and it’s uncertain whether he will return this season.

Stone still has pain in his shoulder and has not been able to start a throwing program since going on the injured list after his Aug. 31 start in Arizona.